5. Female subjects of childbearing potential and male subjects and their partners of childbearing potential, agree to pregnancy prevention throughout the duration of the study (through the Final Visit). Subjects and their partners must agree to use of an effective method of contraception, to avoid impregnation of females throughout the course of the study. Subjects using oral contraceptives must be on a stable regimen for at least 3 months prior to Screening. While the best way to avoid pregnancy is to abstain from sexual activity, adequate forms of contraception to be used include oral contraception, depot contraception, intrauterine device (IUD), and barrier contraceptive methods, such as condoms and barrier creams/contraceptive jellies, and spermicidals. Subjects and their partners who can become pregnant must use contraception while on study drug from admission to the Final Visit. Male subjects must also refrain from donating sperm from admission to the Final Visit